1. Field of the Invention
The present invention relates to an operating device, a control panel including the operating device, and an image forming apparatus including the control panel.
2. Discussion of the Background
In general, multi-function machines combining two or more of copying, printing, and facsimile functions are used as image forming apparatuses.
Typically, operation devices (e.g., control panels) for the image forming apparatuses include multiple keys and at least one liquid crystal display (LCD), and are used to input and display information, execute instructions, carry out various settings, and so forth.
Certain known operating devices include a so-called D-pad key, in which keys are disposed in four directions, right, left, up, and down.
Examples of keys used in certain known operating devices (input devices) are shown in FIGS. 8A, 8B, 8C, 8D, 8E, 9A, 9B, 9C, and 9D.
In the example shown in FIG. 8A, a disciform input key 211 is disposed, and by pressing the disciform input key 211 in four directions, various functions are executed. In this example, letters “OK” 212, representing the function to execute the selected menu item displayed on a LCD, are located on a right side of the disciform input key 211; a mark “▴” 213 representing the function to move up a list of menu items displayed on LCD is located on lower side of the disciform input key 211; a mark “▾” 214 representing the function to move down the list of menu items displayed on LCD is located on lower side of the disciform input key 211; and a return mark “←” 215 representing the function to move back the list of menu items displayed on the LCD 24 is located on a left side of the disciform input key 211.
However, in this example, because the input key 211 is integrated as a single continuous annular unit, users cannot press the disciform input key 211 in two or more directions at once.
Certain known image forming apparatuses include the above-described direction keys in their operating devices. More specifically, a pair of vertical direction keys facing each other and a pair of lateral direction keys are integrated as a single key unit. The vertical direction keys are used to select operating mode, and the lateral direction keys are used to change setting amount of operating mode.
However, in the above-described configurations in which the multiple keys are formed in a single integrated button, although the relation between keys is clearer there is the problem that, because multiple keys are operated by the identical button, users frequently press the wrong key. Further, users cannot press at least two of those keys at once, and therefore operations requiring simultaneous operation of more than one button cannot be executed.
A different problem arises when the keys are not continuous but separated, as shown in FIGS. 8B-8D. An operating device 220 shown in FIG. 8B includes four independent ellipsoidal input keys 221, 222, 223, and 224. On the operating device 220, letters “OK” are displayed beneath the right input key 221, mark “▴” 226 is displayed on the upper input key 222, the mark “▾” 228 is displayed on the lower input key 224, and the return mark “←” is displayed above the left input key 223.
An operating device 230 shown in FIG. 8C includes four independent round input keys 231, 232, 233, and 234. On the operating device 230, letters “OK” 235, marks “▴” 236 and “▾” 237, and a return mark “←” 238 are displayed similarly to the operating device 220.
An operating device 240 shown in FIG. 8D further includes a menu button 245, an escape button 246, and an OK button 247, in addition to four independent round input keys 241, 242, 243, and 244 on which the respective four directions are displayed.
In the above-described examples, because the operation keys are completely independent from each other, it is difficult for the users to grasp the relations among the respective input keys.
An operating device 250 shown in FIG. 8E includes four independent round input keys 251, 252, 253, and 254 on which the respective four directions are displayed. A pattern 255 that shows relationship among the direction input keys 251, 252, 253, and 254 is printed on a surface of the operating device 250.
However, in the above-described example, because there are no indicators for operation, the user cannot correctly press the input keys without looking up a LCD.
An operating device 260 shown in FIG. 9A includes a continuous annular key 261 that is integrated as a single continuous annular unit having four parts divided by four grooves 261a, 261b, 261c, and 261d. A user selects four (right, left, up, and down) directions by pressing the divided four parts. An “OK” button 262 is provided in a center portion of the continuous annular key 261, and a “Menu” button 263, “Sheet/Set” button 264, a “Return” button 265, and a “Trimming” button 266 are provided to surround the continuous annular key 261.
An operating device 270 shown in FIG. 9B includes a continuous annular key 261 that is integrated as a single unit and on which four projection portion 271a, 271b, 271c, and 271d are formed. Additionally, the upper projection 271a is for jobs selection as indicated by letters “Job” 272; the left projection 271b is for utility setting as indicated by letters “Utility” 273; the lower projection 271c functions is for reset as indicated by letters “Reset” 274; and the right projection 271 is for set up as indicated by letters “Set up” 275. An “OK” button 276 is provided in a center portion surrounded by the continuous annular key 271.
An operating device 280 shown in FIG. 9C includes a rounded-rectangular key 281 used to select up and down as well as to search phonebook and call up abbreviated addresses; and two input keys 282 and 283 used to select left and right as well as to increase and decrease volume. Additionally, “Menu” button 284, “Escape/Back” button 285, and “OK” button 286 are provided on the operating device 280.
An operating device 290 shown in FIG. 9D includes four quarter sector-shaped direction keys 291, 292, 293, and 294 that are arranged in a discontinuous annular shape and used to select right, left, up, and down. Additionally, a “Return” button 295 and an “OK” button 296 are provided on the operating device 290.
However, in this example, the user must look up an LCD whenever the operation keys are used because the indicator indicating the name of the function is not provided adjacent to the direction keys 291, 292, 293 and 294. Moreover, in the above-descried examples shown in FIG. 9A through 9D, because the indicators or the buttons are provided outside the direction keys, a large space is required, and thus, flexibility on design is limited, which is not desirable.